Synthetic positive controls for ELISA test kits for detection of IgA and IgM antibodies to Chlamydia trachomatis
AbstractThe enzyme-linked immunosorbent assay (ELISA) is the most informative and versatile method of serological diagnostics. The possibility of detecting by ELISA specific antibodies of different classes allow to differentiate primary infectious process and its remission, exacerbation and chronic disease (holding of differential diagnosis). This approach is implemented in the methodology for evaluation of patients for presence of humoral immune response against the causative agent of urogenital chlamydiosis. As with other infections immediately after Chlamydia trachomatis infection the specific IgM antibodies are formed, and subsequently basic projective antibodies of IgG class are synthesized. However, at exacerbation of chronic urogenital chlamydiosis specific IgA antibodies can be synthesized. That is why comprehensive evaluation of patients for presence of humoral immune response to Ch. trachomatis involves plasma testing of specific antibodies of all three classes. The essential problem in the production of ELISA diagnostic kits is obtaining of positive control. The classic version of positive control is human blood plasma containing specific antibodies. But specific IgM- and IgA-positive sera are deficit raw materials. This fact can significantly limit the production of diagnostic kits, especially in case of large-scale manufacture. We have suggested methodological approach to use of synthetic positive controls in indirect ELISA kits based on conjugate of normal human IgM (IgA) and monoclonal antibodies against major outer membrane protein of Ch. trachomatis. It was found that it’s possible to realize such task by means of NHS ester-maleimide-mediated conjugation (by sulfosuccinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate) and reductive amination-mediated conjugation (by sodium periodate). It was found that synthetic positive controls obtained by different methods are characterized by higher titer compared to IgM- and IgA-positive high-titer serum. However, positive control obtained by NHS ester-mediated maleimide conjugation has the best titration profile characteristics, at the release time and after one-week storage at37 °C.
Dhar, T.K., Dasgupta S., Ray, D., Banerjee, M., 2012. A filtration method for rapid preparation of conjugates for immunoassay. J. Immunol. Methods. 385, 71–78. >> doi:10.1016/j.jim.2012.08.009
Filippovich, J.B., 1999. Osnovy Biohimii [Fundamentals of Biochemistry]. Agar, Moscow.
Galkin, O.Y., 2010. Approaches to the synthesis of conjugates for enzyme immunoassay test-systems and evaluation of their use for diagnostics of infectious diseases. Ukr. J. Clin. Lab. Med. 5(4), 54–60.
Galkin, O.Y., 2014. Parametry bioanalitychnoyi standartyzatsiyi zasobiv dlya serolohichnoyi diahnostyky [Parameters for bioanalytical standardization of medical devises for serological diagnostics]. Materialy IV Naukovo-Praktychnoyi Konferentsiyi “Suchasni Dosyahnennya Farmatsevtychnoyi Tekhnolohiyi” [Proc. 4th Sci. Conf. “Recent advances in pharmaceutical technology”]. Publishing House of the National University of Pharmacy, Kharkov (in Ukrainian).
Galkin, O.Y., Dugan, O.M., 2014. Recombinant heat shock protein of Chlamydia trachomatis: Perspectives of usage in serological diagnostics. Materialy Mizhnarodnoyi Naukovoyi Konferentsiyi “Mekhanizmy Funktsionuvannya Fiziolohichnykh System” [Proc. Sci. Conf. “The Mechanisms of Physiological Systems Functioning”]. Lviv National University, Lviv.
Galkin, O.Y., Gorshunov, Y.V., 2014. Otsinka metodiv biokon’yuhatsiyi dlya otrymannya syntetychnykh pozytyv-nykh kontroliv dlya imunofermentnoho analizu modyfikatsiyi “IgM-pastka” [Evaluation of bio-conjugation methods for obtaining of synthetic positive control for IgM-capture ELISA]. Vìsn. Dnìpropetr. Unìv. Ser. Bìol. Med. 5(2), 85–89.
Harlow, E., Lane, D., 1988. Antibodies. A laboratory manual. Cold Spring Harbor, N.-Y.
Hermanson, G.T., 2000. Bioconjugate techniques. Academic Press, San Diego.
Isakov, V.A., Kuljashova, L.B., Berezina, L.A., Svarval’, A.V., 2012. Laboratornaja diagnostika urogenital’nogo hlamidioza. Sovremennye metody diagnostiki hlamidijnoj infekcii (analiticheskij obzor) [Laboratory diagnosis of urogenital chlamydiosis. Modern methods of diagnosis of chlamydial infection (analytical review)]. Terra Medica 27, 8–13 (in Russian).
Johnstone, A., 1997. Immunochemistry 2: A practical approach. IRL Press, Oxford.
Kamel, R.M., 2013. Screening for Chlamydia trachomatis infection among infertile women in Saudi Arabia. Int. J. Womens Health 5, 277–284. >> doi: 10.2147/IJWH.S46678
Nikolayenko, I.V., Galkin, O.Y., Grabchenko, N.I., Spivak, M.Y., 2005. Preparation of highly purified human IgG, IgM, and IgA for immunization and immunoanalysis. Ukrainica Bioorganica Acta 3(2), 3–11.
Ossewaarde, J.M., de Vries, A., van den Hoek J.A., van Loon, A.M., 1994. Enzyme immunoassay with enhanced specificity for detection of antibodies to Chlamydia trachomatis. J. Clin. Microbiol. 32(6), 1419–1426.
Taylor-Robinson, D., 1997. Evaluation and comparison of tests to diagnose Chlamydia trachomatis genital infections. Hum. Reprod. 12(11), 113–120.
Tijssen, P., 1985. Practice and theory of enzyme immunoassays. Lab. Tech. Biochem. Mol. Biol. 15, 674–678.
Zupanec, I.A., Misjureva, S.V., Propisnova, V.V., 2005. Klinicheskaja laboratornaja diagnostika: Metody issledovanija [Clinical laboratory diagnostics: Research methods]. Publishing House of the National University of Pharmacy, Kharkov (in Russian).
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